/*
 * Licensed to the OpenAirInterface (OAI) Software Alliance under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The OpenAirInterface Software Alliance licenses this file to You under 
 * the Apache License, Version 2.0  (the "License"); you may not use this file
 * except in compliance with the License.  
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 *-------------------------------------------------------------------------------
 * For more information about the OpenAirInterface (OAI) Software Alliance:
 *      contact@openairinterface.org
 */

#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>


#include "TLVEncoder.h"
#include "TLVDecoder.h"
#include "AccessPointName.h"

int
decode_access_point_name (
  AccessPointName * accesspointname,
  uint8_t iei,
  uint8_t * buffer,
  uint32_t len)
{
  int                                     decoded = 0;
  uint8_t                                 ielen = 0;
  int                                     decode_result;

  if (iei > 0) {
    CHECK_IEI_DECODER (iei, *buffer);
    decoded++;
  }

  ielen = *(buffer + decoded);
  decoded++;
  CHECK_LENGTH_DECODER (len - decoded, ielen);

  if ((decode_result = decode_bstring (accesspointname, ielen, buffer + decoded, len - decoded)) < 0)
    return decode_result;
  else
    decoded += decode_result;

  return decoded;
}

int
encode_access_point_name (
  AccessPointName accesspointname,
  uint8_t iei,
  uint8_t * buffer,
  uint32_t len)
{
  uint8_t                                *lenPtr = NULL;
  uint32_t                                encoded = 0;
  int                                     encode_result = 0;
  uint32_t                                length_index = 0;
  uint32_t                                index = 0;
  uint32_t                                index_copy = 0;
  uint8_t                                 apn_encoded[ACCESS_POINT_NAME_MAXIMUM_LENGTH] = {0};

  /*
   * Checking IEI and pointer
   */
  CHECK_PDU_POINTER_AND_LENGTH_ENCODER (buffer, ACCESS_POINT_NAME_MINIMUM_LENGTH, len);

  if (iei > 0) {
    *buffer = iei;
    encoded++;
  }

  lenPtr = (buffer + encoded);
  encoded++;
  index = 0;                    // index on original APN string
  length_index = 0;             // marker where to write partial length
  index_copy = 1;

  while ((accesspointname->data[index] != 0) && (index < accesspointname->slen)) {
    if (accesspointname->data[index] == '.') {
      apn_encoded[length_index] = index_copy - length_index - 1;
      length_index = index_copy;
      index_copy = length_index + 1;
    } else {
      apn_encoded[index_copy] = accesspointname->data[index];
      index_copy++;
    }

    index++;
  }

  apn_encoded[length_index] = index_copy - length_index - 1;
  bstring bapn = blk2bstr(apn_encoded, index_copy);

  if ((encode_result = encode_bstring (bapn, buffer + encoded, len - encoded)) < 0) {
    bdestroy(bapn);
    return encode_result;
  } else {
    encoded += encode_result;
  }
  bdestroy(bapn);
  *lenPtr = encoded - 1 - ((iei > 0) ? 1 : 0);
  return encoded;
}

void
dump_access_point_name_xml (
  AccessPointName accesspointname,
  uint8_t iei)
{
  OAILOG_DEBUG (LOG_NAS, "<Access Point Name>\n");

  if (iei > 0)
    /*
     * Don't display IEI if = 0
     */
    OAILOG_DEBUG (LOG_NAS, "    <IEI>0x%X</IEI>\n", iei);
  bstring b = dump_bstring_xml (accesspointname);
  OAILOG_DEBUG (LOG_NAS, "%s</Access Point Name>\n", bdata(b));
  bdestroy(b);
}
